MYOG - Custom Backpack Design

Drawings for the Mk2 Prototype

While I've finally settled on gear that works for the photography I do, I've long been plagued by the inconvenience of carrying so much gear, in such large formats, over long distances and extreme terrain.

My recent mountaineering trip to Snowdonia in -9 degrees, high winds and semi-consolidated ice where I was attempting some grade 2 and 3 scrambles highlighted that this is something I need to address sooner rather than later.

My current solution has largely been to use an oversized trekking pack that serves me well for the most part, but is not well adapted to the specific requirements of mountain photography, nor even my more static work on lap based event courses. I've been used the Deuter Aircontact Ultra 50+5. As the name suggests, at 50 litres it's pretty overkill for photography day trips, even when carrying full winter gear, ropes and emergency supplies, relying on compression straps and dealing with load shifting around in the bag. It's better suited for 3-5 day thru-hiking trips, or perhaps doing the weekly food shop for my partner and I.

I purchased this primarily because it's one of few packs in the sub 60 litre range with a truly adjustable back system. As a taller guy, I sit outside of torso ranges for almost all one-size packs and most M/L combo sizes. Back in the army, your kit is centred around hip mounted webbing, this webbing should sit low on the hips to avoid bouncing around, and to permit wearing a 70+ litre bergen on top. This has reflected itself in how I find packs most comfortable to wear in civilian kit, with the hip straps sitting a little lower than most people. Mix that with a long torso, and pretty much any pack smaller than 65L in a size L/XL won't sit right for me. A low sitting pack also works well for mountaineering work, as it means you can look up while wearing a helmet to belay etc, without needing to fight with the rucksack sitting high on your shoulders.

The 50+5L being somewhat underutilised on a recent trip. Even with compression straps fully cinched down, it sits loose and proud, not great for scrambling stability or keeping camera gear away from rock faces.

As well as sizing to consider, mountaineering & photography as a combined sport presents issues in terms of weight. Most alpine, mountaineering or climbing packs are only designed to carry about 7-8kg before becoming uncomfortable, and for the most part it's soft / flexible gear like layers, food, ropes and harnesses. Adding a camera into the mix suddenly can double that expected load, with my camera setup weighing 6-8kg alone, depending on which lenses I'm choosing to carry. My kit should all still sit in the 28-35L range, but weigh almost twice what you'd expect a pack of that size.

This leaves me with a specific set of criteria for my perfect bag:

• 1) - 28-35L Capacity - maintain a low profile on technical climbs, and securely store camera gear.

• 2) - Comfortable carrying 12-14kg loads - will utilise a rigid frame sheet, and substantial hip belts to distribute the load.

• 3) - Highly abrasion resistant - all of my larger bags have been snagged on sharp rocks during climbs several times, and I do not want a hole tearing large enough to start losing camera gear.

• 4) - One-handed access to my camera - A lot of my photography relies on getting into positions and reacting to potential shots quickly, I need to be able to grab the camera easily and quickly from within the bag.

• 5) - All the necessary attachments for holding rope, harnesses, crampons, ice axes etc. Ideally removable for summer climbs and to minimise snagging.

To solve this, my design is broken down into 5 key areas:

1 - Geometry. Designs quickly moved towards a tapered shape, with lifted bottom panel, and a fairly shallow depth. The end profile fits within a 60 x 30 x 17cm volume, with a 4cm lift from the base to the front panel, 3cm vertical taper, and a 3cm taper from back to front. This should reduce overhanging components, and ensure corners are tucked in away from rocks while also keeping the centre of mass close to my body. It also allows plenty of room for my full torso length, and load lifter straps.

2 - Load Bearing

Continuing on, load lifters will be essential to keep the pack comfortable at full load, which in turn will need a frame sheet high enough to provide functional lift. Load lifters on packs without a rigid frame sheet are purely a gimmick, so this is essential. To be most effective, I will need an additional 3 inches or so of height above the torso length, hence the circa 60cm height. With this, I'll also need padded shoulder and waist straps, composing of 6mm NBR foam with Gridstop outer and spacer mesh inner.

3 - Material

To maintain abrasion resistance and minimise weight, I'll be making this from UHMWPE (Ultra High Molecular Weight Polyethylene, brand named Dyneema) based fabrics. Specifically the range made by Challenge Sailcloth, Ultra 400 for the most exposed areas and outer fabrics, UltraGrid for inner pockets and strap outers, and UltraStretch for any pockets. These have some of the best strength to weight ratios of any fabrics, as well as water resistance and some bold textures.

4 - Closure

I've struggled with designing a closure that retains water resistance, securely cinches gear down, but can also be opened in a single motion, with my left hand, so that my right hand can immediately reach in to grab the camera.

Most ultralight mountain packs these days use roll top closures for simplicity and water resistance. The cynical part of my brain assumes the former is more to blame for this, as these as incredibly simple and inexpensive to produce. This won't work for me however. A zip offers too much risk of snagging, breaking in cold temperatures and no real possibility for compression. Which leaves a more traditional brain and drawcord method. I dislike bulky brains, I find the bag is rarely full enough to prevent whatever is in the brain sliding around, and they're usually not fast to open, especially with a separate drawcord beneath. Mountain Hardware produce the Scrambler pack, which has an integrated brain/top flap / draw cord system that appears to open in a single motion, which I'm aiming to emulate, but with the top flap being removable where possible. Essentially it is designed that opening the flap also loosens the drawcord, and expands this out as the flap is lifted. I would like the design to have similar function, but allow for the flap to be separated from the draw cord to better allow "top flapping" gear, as well as removable when not necessary.

5 - Mounting

I want the option to increase functionality as much as possible, which external mounts for any gear I might need, ice axe, crampons, ropes, helmets, emergency gear etc, while also minimising permanent fixtures to go ultralight and minimise snags when wanted.

For this, my primary static features will be a front based daisy chain, with low profile webbing loops against the back. I'll also use lay flat embedded tabs, for attaching heavier gear at less frequent points, sufficiently reinforced to handle something like skis, snowboards, etc.

The exterior will also feature a dedicated sleeve to retain ice axes and walking poles, that I must be able to use without taking the pack off. The other side will have a water bottle pouch that is side loaded, rather than top to prevent snagging and snow ingress.

Prototypes:

Multiple prototype stages were produced to get a feeling for geometry, materials and usage.

The first prototype was made from Tyvek House wrap, a lightweight polymer composite that behaves largely like a papery fabric. This helped refine general geometry, fit and features.

The second prototype used Tyvek to simulate areas that would eventually be made from Ultra 400, some cheap light gauge ripstop nylon to replicate the Ultragrid. Some old lycra cycling shorts for Ultrastretch components. This prototype was cut, stitched and built as a direct 1:1 version of my design to test and use in the real world, mindful of the limited durability of the prototype materials.

Standard kit for a winter day in the mountains.

The prototype was loaded up with all of my typical gear, as well as used for some gorp-core style commutes to work, trips to the gym, and some photography gigs for various clients to get a feeling for the size, shape and materials, as well as the functionality of various fixtures and fittings.

Mk2 Prototype fully loaded. Axe sleeve and bottle pouch accessible on the back but with minimum snagging points

Ice axe sleeve occupied and the stash sleeve holding waterproofs. Crampons taking some daisy chain slots.

There were inaccuracies, mistakes and some refinements to be made. The bag was used daily for around 2 months before committing to a final design, and has informed the final design before moving onto the expensive real materials. An entire page of my notebook was dedicated to observations and improvements before moving onto the final design.